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Item Clinical Evaluation of a Universal Adhesive in Non-Carious Cervical Lesions(2016) Rouse, Matthew A.; Platt, Jeffrey A.; Jackson, Richard D.; Carlson, Timothy J.; Matis, Bruce A.; Cook, Norman BlaineThe “total-etch” or “etch-and-rinse” systems have been the gold standard of dental bonding for decades. However, these systems are very technique-sensitive and time-consuming compared to newer “self-etch” or “self-adhesive” systems and have been implicated in cases of postoperative sensitivity. The purpose of this study was to compare the effects of two surface treatment protocols (self-etch vs. selective-etch) on the clinical performance of a universal adhesive and resin composite in Class V non-carious cervical lesions (NCCLs). Thirty-three volunteer subjects (17 male; 16 female; age range = 20 to 75 years) having at least two NCCLs were selected from patients of record at Indiana University School of Dentistry. Each subject received one resin composite restoration (Tetric EvoCeram, Ivoclar Vivadent) utilizing a self-etch (SfE) universal adhesive (Adhese Universal, Ivoclar Vivadent) with no separate enamel etching and another restoration utilizing adhesive and selective enamel etching (SelE) with 37% phosphoric acid (H3PO4). Both the adhesive and composite were placed following the manufacturer’s instructions. The two techniques were compared for differences in sensitivity, retention, marginal discoloration, marginal adaptation, and clinical acceptability at baseline and 6 months using the Cochran-Mantel-Haenszel tests for stratified, ordered categorical outcomes. Seventy-four restorations (37 SfE, 37 SelE) in 30 volunteers were evaluated at 12 months. No significant differences were found between the SfE and SelE groups for any variable at the 12-month recall (p>0.21). Retention was 100% at 12 months for both groups. Marginal adaptation was significantly worse at 12 months than at baseline for SelE (p=0.0163), but there was no difference for SfE (p=0.08). Sensitivity improved significantly from baseline to 12 months for both SelE (p=0.0113) and SfE (p=0.0128). The results obtained from this study are comparable to results observed in similar studies. Like similar studies involving self-etch adhesives in non-carious cervical lesions, our study showed no restorations lost to caries and excellent retention. The deterioration of selective-etch dentin margins was a result that differed from similar studies. A likely explanation for this finding would be the difficulty of controlling precise placement of phosphoric acid gel, causing undesired etching of dentin; this could result in suboptimal bonding to dentin. This report on 12-month data for a two-year study indicates significantly reduced sensitivity for both the SelE and SfE groups, and deterioration of SelE marginal adaptation. No decreases in retention, marginal discoloration, or clinical acceptability were observed in either group.Item Combined Effects of Soda Drinks and Nicotine on Streptococcus Mutans Metabolic Activity and Biofilm Activity(2019) Mokeem, Lamia Sami; Gregory, Richard; Cook, Norman Blaine; Windsor, Jack; Eckert, GeorgeItem Cuspal Deflection in Premolar Teeth Restored with Bulk-Fill Resin-Based Composite Materials(2015) Elsharkasi, Marwa M.O.; Platt, Jeffrey A.; Cook, Norman Blaine; Hara, Anderson T.; Matis, Bruce A.; Bottino, MarcoObjectives: To investigate the effect of bulk-fill resin based composite materials on cuspal deflection in large slot mesio-occlusal-distal cavities (MOD) in premolar teeth. Methodology: Thirty-two sound maxillary premolar teeth with large slot MOD cavities were distributed to four groups (n=8). Three groups were restored with bulk-fill resin composite materials (Tetric EvoCeram, x-tra fil, and Sonic Fill, respectively) in a single increment. The conventional composite group, Filtek Z100, was used to restore the cavities in 2mm increments. Cusp deflection was recorded post irradiation using a Nikon measurescope UM-2 (Nikon, Tokyo, Japan), by measuring the changes in the bucco-palatal width of the premolar teeth at 5 minutes, 24 hours, and 48 hours after completion of the restoration. The cuspal deflection was obtained by recording the difference between the baseline measurements and the other measurements for each tooth. Results: Cuspal deflection was significantly higher in Conventional Composite than in Tetric EvoCeram Bulk Fill (p=0.0031), x-tra Fil Bulk (p=0.0029), and SonicFill Bulk (p=0.0002). There was no significant difference in cuspal deflection for Tetric EvoCeram Bulk, X-tra Fil Bulk, and SonicFill Bulk Composites. Conclusions: All the investigated bulk-fill resin composites exhibited cuspal deflection lower than conventional resin composite. One of the aims of research and studies on the resin composite materials is improving their clinical longevity, and simplifying their use. For that purpose bulk-fill materials are considered promising materials and further clinical studies should be conducted.Item Degradation of bleaching agents under two different storage conditions(2016) Almutiri, Basil; Cook, Norman Blaine; Platt, Jeffrey A.; Lund, Melvin R.; Soto, Armando E.; Matis, Bruce A.This study was conducted in order to determine if there is any change in the active ingredient of tooth-whitening agents when the products are received from the manufacturer (Baseline), two months, four months, and six months after they are received, under two different storage conditions. Thirty-six products were received from multiple manufacturers: eight with hydrogen peroxide and 28 carbamide with peroxide products. All the bleaching syringes for a specific product were from the same lot. Once the products were received, one sample of each product was stored at room temperature and the other sample was stored in a refrigerator. Assays to determine the baseline concentration were performed within the first two weeks of their arrival and again 2 months, 4 months, and 6 months after receiving the products. All samples were analyzed for peroxide content by using the United States Pharmacopeia recommended method. The results obtained from this study show the following: 1. Bleaching products have different concentrations than what are indicated on the label. 2. Storage of bleaching products for an extended time at room temperature can cause bleaching products to lose some of their potency. 3. The preferable storage condition verified in this study is under refrigeration.Item Effect of nicotine on biofilm formation of streptococous mutans isolates from smoking versus non-smoking human subjects(2017) El-ezmerli, Nasreen Farouk; Gregory, Richard L.; Hara, Anderson T.; Cook, Norman Blaine; Windsor, Jack L.Tooth decay is a complex dieto-bacterial disease with an association of social, behavioral and biological factors. Streptococcus mutans plays a major role in tooth decay. This endogenous oral microorganism adheres to tooth surfaces and grows and develops into micro-communities that mature and form dental biofilm. Development of cariogenic biofilm is one of the major factors associated with the tooth decay process. The use of tobacco is considered a great risk factor for oral diseases. Several studies demonstrated the association of tooth decay and the use of tobacco as effects of first-hand or second- hand smoking. Nicotine has been reported to increase the biofilm growth and metabolism of S. mutans in a dose-dependent manner up to 16 mg/ml of nicotine. However, its effects on biofilm formation of S. mutans strains isolated from smokers are not known and should be investigated. Therefore, we proposed the use of an in-vitro model to better understand the effects of nicotine on biofilm formation of strains of S. mutans isolates from smokers versus non-smoking subjects. Objectives: To investigate the effects of nicotine on biofilm formation of S. mutans isolates from oral washes of smoker and non-smoker human subjects. Materials and Methods: This study was conducted using three S. mutans isolates collected from oral washes of 10 smoking subjects and 10 non-smoking subjects. The oral wash samples were stored at -80oC before S. mutans isolation. S. mutans isolates were obtained by plating on Mitis Salivarius Sucrose Bacitracin plates and species identity confirmed by carbohydrate fermentation assays. Nicotine from Sigma-Aldrich (St. Louis, MO, USA) was used. Biofilm was formed by overnight culturing of each S. mutans strain (10 μl) in 190 μl of tryptic soy broth (TSB) supplemented with 1.0-percent sucrose (TSBS) containing 0 mg/ml, 0.25 mg/ml, 0.5 mg/ml, 1.0 mg/ml, 2.0 mg/ml, 4.0 mg/ml, 8.0 mg/ml, 16.0 mg/ml, and 32.0 mg/ml of nicotine for 24 hours in 5.0-percent CO2 at 37oC in sterile (8 x 12) 96-well microtiter plates (Fisher Scientific, Newark, DE, USA). The absorbance values of biofilm were measured at 490 nm in a microplate spectrophotometer (SpectraMax 190; Molecular Devices, SunnyVale, CA, USA) after crystal violet staining. Null Hypotheses: 1) Nicotine will not increase biofilm formation in both smoker and non-smoker S. mutans isolates. 2) An increase in nicotine concentrations will not increase biofilm formation in both smoker and non-smoker S. mutans isolates in a dose-dependent manner. 3) Nicotine will not produce significant differences in biofilm formation between smoker and non-smoker S. mutans isolates. Alternative Hypotheses: 1) Nicotine increases the growth of biofilm formation in both smoker and non-smoker S. mutans isolates. 2) An increase in nicotine concentrations increase biofilm formation of both smoker and non-smoker S. mutans isolates in a dose-dependent manner. 3) However, nicotine increases biofilm formation of smoker S. mutans strains more than non-smoker S. mutans isolates. The rationale for this hypothesis is that our preliminary data indicated that S. mutans can become resistant to increased nicotine concentrations and that this resistance appears to be stable and may allow the smoker isolates to be able to respond more vigorously to higher nicotine concentrations than the non-smoker isolates. Results: There was a significant effect (p < 0.05) of both nicotine concentrations and smoking on the growth of biofilm, planktonic cells, and total absorbance, for all strains of S. mutans (p < 0.0001). Isolates from smokers had significantly more biofilm at 0 mg/ml to 16 mg/ml of nicotine compared with those from non-smokers (p-value < 0.0001). Conclusion: S. mutans smoker isolates are more affected by high nicotine concentrations than non-smoker isolates.Item The effect of pit and fissure morphology and sealant viscosity on sealant penetration and microleakage(2017) Zawam, Omelkher Muftah; Soto, Armando E.; Hara, Anderson T.; Cook, Norman BlaineBackground: The ability of sealants to prevent caries is directly related to the sealant being retained in teeth. The longer the material remains bonded to the occlusal surface, the more protection it provides to the tooth. Objective: The aim of this in-vitro study was to evaluate the influence of pit and fissure morphologies and sealant viscosity on sealant penetration and micro-leakage. 82 Study Hypothesis: The low viscosity dental sealant will express better penetration ability and less microleakage in permanent molars with any pit and fissure morphology than the high viscosity sealant. Material and methods: Permanent extracted molars (n = 150) were distributed into two groups based on two types of sealant (high and low viscosity) Permanent extracted molars (n = 150) were selected using the International Caries Detection Assessment system (ICDAS) criteria 0-1. Teeth were stored in 0.1-percent thymol and distilled water. Teeth were assigned to three subgroups according to the fissure’s morphology. Enamel was etched with 35-percent phosphoric acid for 30 seconds; two different light cured sealants were placed, Group A: Delton and Group B: Ultra X Plus. Specimens were thermocycled for 500 cycles between two water baths, having a 40°C temperature differential (4°C to 48°C). Teeth were coated with nail varnish and wax, except in the occlusal areas. All specimens were immersed in 1-percent methylene blue dye at 37°C for 24 hours. Specimens were sectioned longitudinally in a bucco-lingual direction, and the sections were photographed and analyzed by a previously trained examiner for fissure morphology, sealant penetration, and microleakage using a standardized grading system. Data were entered and statistically analyzed, at the 5-percent significance level. Results: Viscosity of sealant and morphology of fissures had significant effects on sealant penetration (p < 0.001). The interaction between viscosity of sealant and morphology of fissures was not significant (p = 0.4236). The sealant penetration for Delton was significantly higher than the UltraSeal XT Plus (p < 0.0001). The sealant penetration for fissure I-type was significantly lower than fissures U and V-types (p < 0.0001). Sealant penetration for Y-type was significantly lower than U and V-types (p < 83 0.0001). However, the viscosity of sealant and morphology of fissures did not have significant effect on microleakage (p = 0.5891 and p = 0.4857). The interaction between the viscosity of the sealant material and the morphology of pit and fissures was not significant (p = 0.6657). Conclusion: The results of the present study indicated the viscosity of the sealant and the morphology did not affect the microleakage. On the other hand, the viscosity of sealant affected the penetration ability of dental sealant. The low viscosity dental sealant (Delton) exhibited a better penetration than the high viscosity sealant (UltraSeal XT Plus). As the morphology of pit and fissure directly affected the penetration ability, the fissures types U and V exhibited a better penetration than fissure types Y and I.Item Effect of Toothbrushing on a Monolithic Dental Zirconia Submitted to an Accelerated Hydrothermal Aging(2022) Almajed, Norah; Sochacki, Sabrina Feitosa; Cook, Norman Blaine; Capin, Oriana ReisItem Effects of Cinnamon Water Extract as a Cariostatic Agent on Nicotine-Induced Streptococcus Mutans Biofilm(2019-03) Alshahrani, Abdulaziz; Gregory, Richard L; Lippert, Frank; Cook, Norman BlaineObjective: The aim of this study is to investigate the effects of cinnamon water extract on nicotine-induced Streptococcus mutans biofilm. This study utilized S. mutans biofilm assays with varying concentrations of nicotine/cinnamon water extract levels. Design: A preliminary experiment was carried out to confirm the most likely effective concentration of cinnamon water extract on S. mutans biofilm. Then a 24-hour culture of S. mutans UA159 in microtiter plates was treated with varying nicotine concentrations (0-32 mg/ml) in TSBS at the same time with or without the optimum cinnamon water extract concentration. A spectrophotometer was used to determine total growth absorbance and planktonic growth. The microtiter plate wells were washed, fixed and stained with crystal violet dye and the absorbance measured to determine biofilm formation. Results: The results indicated that cinnamon water extract was able to inhibit biofilm formation significantly (p<0.05) at 5 mg/ml cinnamon water extract, therefore, 5 mg/ml of cinnamon water extract was recognized as the MIC for S. mutans biofilm formation. When combined with nicotine, cinnamon water extract sub-MIC (2.5 mg/ml) demonstrated a significant inhibitory effect (p<0.05) in biofilm and total absorbance measures at high concentrations of nicotine (8 mg/ml and above). In addition, cinnamon water extract showed a significant effect (p<0.05) at very low concentrations of nicotine (0.25 and 0.5 mg/ml) in all measures (biofilm, planktonic and total absorbance). However, at low concentrations of nicotine (2 and 4 mg/ml), there was a significant increase (p<0.05) in biofilm growth, whereas planktonic growth was significantly (p<0.05) decreased at the same concentrations. Conclusion: These results provided more evidence regarding the negative effects of nicotine and also demonstrated the positive influence of cinnamon water extract in reducing nicotine-induced biofilm formation, which needs be confirmed by in-vivo studies.Item Evaluation of multiple and single emission peak light emitting diode light curing units effect on the degree of conversion and microhardness of resin-based pit and fissure sealant(2017) Alqahtani, Saleh Ali M.; Soto, Armando E.; Platt, Jeffrey A.; Cook, Norman BlaineObjective: The objective was to assess a multiple emission peak light-emitting-diode (LED) light-curing unit (LCU) by measuring the polymerization efficiency through the degree of conversion (DC) and Knoop microhardness (KHN) of a resin-based pit and fissure sealant at various light curing times and two distances compared to a single emission peak LED LCU. Method: Sixty disks of resin-based pit and fissure sealant (Delton, DENTSPLY, York, PA) samples (6x1mm) were fabricated (n=5/LCU/group). Prepared samples were polymerized using 10, 20 and 40 second curing time at 2 or 4 mm curing distances. The irradiance and radiant exposure received on the top/bottom surfaces of the samples were measured using the Managing Accurate Resin Curing-Resin Calibrator (MARC-RC) system. The samples were stored at 37°C for one hour. Then, the DC (n=3/surface) and KHN (n=5/surface) measurements were collected on the top and bottom surfaces using Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) and a microhardness tester (Instron) utilizing 25-gm at 10 seconds dwell time, respectively. Multiple-way ANOVA was performed followed by Tukey test (α=0.05). Result: The irradiance from the multiple emission peak LED LCU was significantly higher than the single emission peak LED LCU (1312.6 and 768.3 mW/cm2) respectively. Moreover, the multiple emission peak LED LCU displayed significantly higher DC (82.5%) and microhardness (26.2 KHN) compared to the single emission peak LED LCU (75.5% DC and 21.2 KHN) when curing samples at 2 and 4 mm curing distances assessed using 10, 20 and 40-second curing times. The 10 second cure at 4 mm showed significantly lower DC and KHN values compared to the other groups. Conclusion: The multiple emission peak LED LCU demonstrated significantly higher irradiance, DC and KHN compared to the single emission peak LED LCU on a resin-based pit and fissure sealant at 2 and 4 mm curing distances and 10, 20 and 40 second curing times. Therefore, the multiple emission peak LED LCU performed higher than the single emission peak LED LCU.Item First-hand nicotine/tobacco exposure on Streptococcus Mutans biofilm and effects of sodium chloride, potassium chloride and potassium iodide salts(2017-05) BalHaddad, AbdulRahman; Gregory, Richard L.; Windsor, L. Jack; Cook, Norman BlaineObjective: The aim of this study is to investigate the effects of first hand nicotine exposure on Streptococcus mutans biofilm formation and the inhibitory effects of sodium chloride (NaCl), potassium chloride (KCl) and potassium iodide (KI) salts. This study examined bacterial growth with varying concentrations of NaCl, KCl and KI salts and nicotine levels consistent with primary levels of nicotine exposure. Design: A preliminary experiment was done to investigate the most likely effective concentration of NaCl, KCl and KI. Then, a 24-hour culture of S. mutans UA159 in microtiter plates was treated with nicotine (0-32 mg/ml) in Tryptic Soy broth supplemented with 1.0-percent sucrose (TSBS) simulating first hand exposure with and without 0.45 M of NaCl, 0.23 M of KCl and 0.113 M of KI. A spectrophotometer was used to determine total growth and planktonic growth. The biofilm was fixed, stained with crystal violet dye and the absorbance measured to determine biofilm formation. Results: The presence of 0.45 M of NaCl, 0.23 M of KCl and 0.113 M of KI significantly inhibited (p<0.05) first hand nicotine-induced S. mutans biofilm formation by 52 percent%, 79.7 percent, and 64.1 percent, respectively. Similar results were obtained for planktonic growth. Conclusion: These results provided more evidence regarding the negative effects of nicotine and also demonstrated the positive influence of these salts in reducing nicotine-induced biofilm formation, which needs be confirmed by in-vivo studies.